Carrier AT&T said it would sell two 4G LTE smartphones -- HTC Vivid and Samsung Galaxy S II Skyrocket -- on its network from Nov.6.

AT&T claims it offers the only smartphones able to utilize both LTE and HSPA+ 4G speeds, for a consistently fast connection in and out of LTE areas. The Nov. 6 launches expand AT&T's 4G LTE network to 9 markets, including Atlanta, Chicago, Dallas-Fort Worth, Houston and San Antonio, and it plans to reach 15 markets and 70 million Americans by year-end 2011. The service will be launched in Boston, Washington, D.C., Baltimore, and Athens, and Georgia too.

Both HTC Vivid and Samsung Galaxy S II Skyrocket run on Android Gingerbread mobile operating system. HTC Vivid sports a dual core 1.2 GHz processor and a brilliant 4.5-inch qHD display along with an 8MP camera optimized for low-light photos and full widescreen HD video.

On the other hand, Samsung Galaxy S II Skyrocket has a 1.5 GHz dual core processor, SuperAMOLED Plus display spanning 4.5-inches and an 8MP rear-facing camera with LED flash, with 2-megapixel front-facing camera.

Let's see how these two LTE variants fare against each other.

Display: HTC Vivid features a 4. 5-inch qHD display with a resolution of 540x960 pixels, while Samsung Galaxy S II Skyrocket touts a 4.5-inch Super AMOLED Plus display that may give a resolution of 800 x 480 pixels with about 207 ppi pixel density.  

Size: HTC Vivid weighs 135 grams and has a dimension of 135.5 x 67.9 x 8.9 mm. On the other hand, Skyrocket comes in 129.8 x 68.8 x 9.5 mm dimension and weighs 130.5 grams.

OS: Both phones run on Android Gingerbread operating system, with Vivid running on Android 2.3.4 and Skyrocket is powered by Android 2.3.5. It is expected that both phones would be upgraded to the latest version of Google Inc.'s smartphone operating system, Android 4.0 Ice Cream Sandwich, after the holiday season.

Processor: Vivid has a 1.2GHz dual-core Qualcomm Snapdragon processor, while Skyrocket features a 1.5 GHz Scorpion dual-core processor, Adreno 220 GPU, Qualcomm APQ8060 Snapdragon chipset with 1GB RAM.

Camera: Both the smartphones sport 8-megapixel LED flash camera with 1080p HD video capture capability, with Skyrocket has a 2MP camera on the front for video calling. Vivid's camera with dual-LED flash with an f2.2 28mm wide angle lens and record high-definition videos at 60 frames per second.

Wi-Fi: Vivid has Wi-Fi 802.11 b/g/n and Wi-Fi hotspot, while Skyrocket will have Wi-Fi 802.11 a/b/g/n, DLNA, Wi-Fi Direct and Wi-Fi hotspot. Both phones have Bluetooth 3.0 version along with mini USB 2.0 version.

Connectivity: Vivid supports HSDPA, HSUPA, LTE networks, while Skyrocket will have HSDPA 21.1 Mbps, HSUPA 5.76 Mbps and 4G LTE support.

Memory: Both phones come with internal memory of 16GB and offers MicroSD card support of up to 32GB.

Pricing: HTC Vivid and Skyrocket will be available for $199.99 and $249.99, respectively under a two-year contract with AT&T.